Choice of primary outcomes evaluating treatment for heavy menstrual bleeding

Abstract

Background: Heavy menstrual bleeding (HMB) is a common problem with a variety of treatment options and many studies have been performed evaluating treatment effects. Consistency in the choice and definition of primary and secondary outcomes is important for the interpretation of data and for the synthesis of data in systematic reviews or individual patient data meta-analysis (IPDMA). Objective: To give insight into the primary endpoints and outcome measures chosen in randomised controlled trials (RCTs) and systematic reviews regarding the treatment of HMB. Search strategy: Published systematic reviews and RCTs. Selection criteria: Full reports of RCTs or systematic reviews. Data collection and analysis: For RCTs, we used the primary outcomes, as they were used for the sample size calculation. For systematic reviews, all outcomes listed as primary were included. Four authors selected the studies. Results: Twelve different primary outcomes were reported by 66 RCTs, most blood loss- related (44/66 studies). Amenorrhoea was the most common blood loss primary outcome (16/44 studies) and the Pictorial Blood Loss Assessment Chart (PBAC) was the most used measurement tool (27/44 studies). Satisfaction was the second most prevalent primary outcome measure (13/66 studies). In all, 14/26 (54%) systematic reviews prespecified a single primary outcome, whereas all other reviews used composite primary outcomes. Blood loss was the most studied outcome (12/26 reviews). Conclusions: The most used primary outcomes in HMB studies relate to blood loss but there is no consistency regarding the endpoints chosen or measurement tools used to describe blood loss. Standardising outcomes will aid valid comparison and interpretation of data pertaining to the treatment of HMB. Tweetable abstract: A standardised collection of outcomes in heavy menstrual bleeding research is urgently needed.